1. Field of the Invention
This invention relates to an information recording-reproducing method and apparatus used for the filing or the like of documents, and is particularly suitable for effecting recording and reproduction using optical discs or the like.
2. Description of the Prior Art
As the means for accumulating information, such as documents and outputs of computers, there are well known information recording-reproducing apparatuses using a semiconductor memory, a magnetic tape, a magnetic disc or the like as a recording medium. In recent years, along with the progress of the information society, increasing the capacity of such recording-reproducing apparatuses has been extensively studied. In particular, those apparatuses which use an optical disc as a recording medium have very promising in that they are excellent information recording density, that the recording-reproducing head is out of contact with the recording medium and this eliminates the possibility of the recording medium and head beng abraded and that the development of magneto-optic materials has made erasing and re-recording possible.
On the other hand, along with the aforementioned tendency of the information recording-reproducing apparatuses toward greater capacities, several search systems for quickly reading out recorded information have been proposed.
The most popular search system uses a separate recording means, such as a mini-floppy disc, and according to this search system, the title, address numbers, etc. of the information recorded on the recordng medium are recorded on the mini-floppy disc or the like and in the case of information search, the title and the address number list are first read out, and then the address number of the information which it is desired to reproduce is selected and reproduced. There are also systems wherein an area in which only the title of information and the address number list are recorded and an area in which the information is recorded are provided on a recording medium and in the case of search, the title and the address number list are read out and the address number of the information which it is desired to reproduce is selected and reproduced.
However, the apparatuses having the separate recording means for searching, as described above, have suffered from problems with respect to the complication, bulkiness and cost of the apparatus, and the method of providing the areas of search information on the recording medium has suffered from a problem that the title and the address number are recorded at two locations and this leads to reduced recording capacity.
Further, even where the search systems as described above are adopted, when the title of desired information is unclear or when it is desired to find out only a necessary portion from the information searched by the title, there has been a desire to directly see the recorded information and moreover quickly search it.